The invention relates generally to mechanisms for preventing removal of cups from liquid-dispensing machines, such as soda-dispensing machines, and more particularly to an iris mechanism for preventing unauthorized removal of cups from apparatus for dispensing a single cup from a stack of cups within the machine.
Apparatus of the type adapted for dispensing a single container, such as a paper cup, from a stack of containers is used in hot and cold drink vendors, for example, to dispense cups to be filled with liquid. Such vending machines are preferably placed in any convenient location for travelers, students, truck drivers, etc., even though many of these locations are not continuously supervised. It is not uncommon, however, for vandals to attempt to remove cups from such machines, either for use or to scatter them around. This problem is especially acute and expensive when vandals remove every cup in the vendor, leaving no cups for legitimate use, or jam the cup dispenser so that cups cannot be dispensed without the machine being serviced.